The invention relates to a method and a damping device for vibration damping of at least one blade of a turbomachine as well as a turbomachine with such a damping device.
Turbomachines, such as airplane engines, commonly have one or more damping devices for vibration damping of their blades. Thus, it is known from the patent DE 4 015 206 C1 to brace the running blades of a blade ring together through their shrouds. For this purpose, the shrouds have, for example, a Z-shaped design with two force-transmitting faces each for mutual mechanical coupling. Known from the patent EP 0 511 022 B1 is to brace the running blades of a blade ring together through a wire-like damping element, which is guided by its blade surfaces. Furthermore, it is known from the patent application EP 1 944 466 A1 to arrange damping elements in pockets of adjacent shrouds. When rotation of the rotor occurs, the damping elements move radially outward owing to centrifugal force and thereby bring about mechanical coupling of the shrouds. In addition, it is known to arrange damping elements in cavities on the blade neck side such that they can move in the axial direction. The damping effect is created owing to the action of friction between the damping element and the respective running blade. Often, however, the contact forces of the damping elements are too small at low speeds of rotation owing to their small mass to achieve an adequate damping effect.